The present description refers to the technical field of syringes or injection cartridges and particularly concerns a pre-filled injection device.
The pre-filled syringes or cartridges, for example the double chamber ones, are known for a long time and nowadays they are used widely. Said double chamber syringes or cartridges include a tubular containment body and two substances, at least one of which is a liquid substance, contained in two initially separated containment chambers, which are defined inside the tubular body.
The two substances, which are for example a solid substance in a powder form and a liquid substance, are intended to be mixed just before being administered/injected to the patient. The liquid substance is for example an injectable solvent. In order to mix the two substances, the two containment chambers are brought in communication in order to reconstruct an injectable solution, for example by providing for a bypass element between the two chambers in the pre-filled syringe or cartridge.
Currently, no pre-filled syringes are known allowing administering/injecting very small doses of a reconstituted solution, for example doses having a volume of about one milliliter or a tenth milliliter. Those doses are required for example to administer antibiotics locally, for example to inject a cephalosporin antibiotic, such as cefuroxime, in the patient's ocular chamber.
There is the need of making a pre-filled injection device, which allows injecting very small doses of a reconstituted solution in an accurate and safe way.